Gastrointestinal cancer represent one of the major reasons for tumor related death in the United States. Current treatment options are limited to surgery, chemotherapy, radiation therapy and molecular targeted therapy and new treatment options are urgently needed. We are enrolling patients on the following studies: NCI-C0120: A Pilot Study of Tremelimumab - A Monoclonal Antibody against CTLA-4 in combination with Trans-Arterial Catheter Chemoembolization (TACE), Radiofrequency Ablation (RFA), Stereotactic Body Radiation Therapy (SBRT) or Cryoablation in Subjects with Hepatocellular Carcinoma (HCC) or Biliary Tract Carcinomas (BTC). This study is almost completed. The treatment led to a 25% response rate. 11-C-0102: A Phase I/II Study of TRC105 in Combination With Sorafenib in Hepatocellular Carcinoma (HCC). This study is completed. Outcome analysis is ongoing. 15-C-0027: A Pilot Study of Immune Checkpoint Inhibition (Tremelimumab and/or MEDI4736) in Combination With Radiation Therapy in Patients With Unresectable Pancreatic Cancer. We are currently enrolling patients in the second cohort